Bitcoin doesn't scale. There's a lot of issues at hand here, but the
most fundemental of them is that to create a block you need to update
the state of the UTXO set, and the way Bitcoin is designed means that
updating that state requires bandwidth equal to all the transaction
volume to keep up with the changes to what set. Long story short, we get
O(n^2) scaling, which is just plain infeasible.